It’s that time of year when candidates for the Minnies are announced. Last year CapeRay’s dual-modality Aceso system was shortlisted for Best New Radiology Device, while this year one of the semi-finalists in this category is MARIA, a breast imaging system based on radio-waves from UK manufacturer, Micrima. The company was spun out from Bristol University in 2006 and since then has developed a number of prototypes of MARIA, conducting clinical trials and securing the CE Mark in 2015.
Instead of X-rays, the system is based on radio-waves and, similar to the whole-breast ultrasound system from Delphinus, the patient lies prone on a bed with her breast hanging under the influence of gravity in the transducer (above right). The MARIA transducer is a concave cup that can accommodate a range of breast sizes and incorporates an array of 60 radio-frequency antennae that surround the breast (below left). Each antenna transmits sequentially and the other 59 record the signal reflected from the underlying tissue, enabling the device to construct a 3D map of the breast.
MARIA takes less than 5 minutes to scan each breast and captures variations in three tissue parameters – impedance, permittivity and conductance – that enable a clinician to differentiate between normal tissue and lesions. In 2016 the collaborators from Bristol University and Micrima published a clinical evaluation of MARIA in the Journal of Medical Imaging. The system was tested on 86 patients who met the inclusion criteria: symptomatic; due to be examined by ultrasound and mammography; able to lie prone; and having a breast size in the range 310 to 850 cm3.
Of the 86 patients, 66 had some type of lesion, with a radiologist who conducted a blind review of the mammograms making a correct diagnosis in 83% of cases, compared with 74% for MARIA. Interestingly, MARIA was more successful for dense breasts (BI-RADS c and d) with a correct diagnosis in 86% of cases compared to the radiologist’s score of 79%. Seen below right is a case (© SPIE) where the mammogram was marked as normal by the experienced radiologist while MARIA correctly identified an invasive ductal carcinoma.
Because radio-waves produce no ionizing radiation and the system does not require breast compression, Micrima believes MARIA holds great potential as a competitor to mammography, especially as it performed better in women with dense breasts. It’s fascinating to think that a technology originally developed to detect buried land mines, might some day find application in detecting breast cancer.
Non feasable for high volume screening. 10 minutes.
Breast size ranges upto 4 liter. (here 0,8)
Cysts?
Radiologist score 79%. Density?
Interesting indeed!
However all the statistics from Maria pale in the face of the D 3-AB US mammography machine which when available be able detect up to 95% of breast cancers in women, with all without dense breast tissue
All we are waiting for now is the CE Mark of approval.
There can be no doubt in my mind that the combination of the
D 3 and ultrasound will be the most superior method of detecting early breast cancers.
Harvard Radiology Prof. Daniel Kopans, a world authority on breast imaging and the inventor of the
D 3 (D B T) feels this machine will be capable of finding 95% of all breast cancers in women with or without dense breast tissue,and will be the mammography machine of the future.
Ian Grant -Whyte MA MD (Cantab)